Oil pressure dropping under high RPM / load ? - LS1TECH

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Oil pressure dropping under high RPM / load ?

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Old 03-08-2010, 09:32 PM   #1
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Default Oil pressure dropping under high RPM / load ?

I noticed once i get over 4,000 RPM and you are foot the floor in 2nd gear, the oil pressure goes down to 25lbs and jumps up to 40 in about 2 seconds. What could be the cause of this? I have a canton pan, and my builder told me to run 7 qts. could the gauge be wrong? It really makes me sick seeing that, especially how i just spent 10k on a new motor..
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Old 03-09-2010, 01:27 AM   #2
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windage man, i have the same problem. try running it with 5-6 quarts and see if it improves...
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Old 03-09-2010, 01:40 AM   #3
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You should also run a high flow filter....

The K&N 3002HP is what I run. It filters excellent and is very high flow.
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Old 03-09-2010, 03:07 AM   #4
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i have this same problem but since my oil pressure never goes low enough to not lubricate the engine, ive not been extremely concerned with it. i have a canton road race pan with a built in windage tray though. so would it still be doing this?
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Old 03-09-2010, 04:20 AM   #5
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I had the same problem with my canton pan. I ended up having to taking out the built in windage tray/screen and putting a moroso windage tray off the main caps to fix it.
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Old 03-09-2010, 05:27 AM   #6
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My first 355 did that, cam bearings were going south. Telltale sign of that is an oil leak on the water pump shaft.
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Old 03-09-2010, 05:35 AM   #7
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I have seen oil pressure vary due to a failing o-ring where the pick up tube hits the block. Just a thought
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Old 03-09-2010, 06:18 AM   #8
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Quote:
Originally Posted by mklinger View Post
I have seen oil pressure vary due to a failing o-ring where the pick up tube hits the block. Just a thought
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Old 03-09-2010, 06:46 AM   #9
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well seeing as how my pickup fell off and thats why i changed the pan/pump, i honestly cant recall if i had this problem with the stock pan. i didnt realize the canton pans had this problem. will definately look into this further. glad i read this thread.
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Old 03-09-2010, 06:51 AM   #10
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Quote:
Originally Posted by mklinger View Post
I have seen oil pressure vary due to a failing o-ring where the pick up tube hits the block. Just a thought
And where would this alleged o-ring be?
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Old 03-09-2010, 06:53 AM   #11
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Quote:
Originally Posted by ls2pontiac View Post
I noticed once i get over 4,000 RPM and you are foot the floor in 2nd gear, the oil pressure goes down to 25lbs and jumps up to 40 in about 2 seconds. What could be the cause of this? I have a canton pan, and my builder told me to run 7 qts. could the gauge be wrong? It really makes me sick seeing that, especially how i just spent 10k on a new motor..
You don't indicate what pump you are using. Aside from windage, it could be cavitation.
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Old 03-09-2010, 07:13 AM   #12
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Quote:
Originally Posted by shbox View Post
And where would this alleged o-ring be?
#2 Where does the pickup bolt TO THE BLOCK?????????????
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Old 03-09-2010, 10:13 AM   #13
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Quote:
Originally Posted by mklinger View Post
I have seen oil pressure vary due to a failing o-ring where the pick up tube hits the block. Just a thought
LOL that's awesome!
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Old 03-09-2010, 10:14 AM   #14
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Melling 10554 with standard spring. I put 6 quarts in this time...hmm. Do you think anything got hurt by it dropping to 30 lbs at almost 6000 rpm real quick a couple of times? It always bounced back within a second or 2.
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Old 03-09-2010, 11:42 AM   #15
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since it only truly takes 8psi of oil pressure to lubricate the small block chevy, id say you should be ok.
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Old 03-09-2010, 12:25 PM   #16
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My car does the same thing, even after it was rebuilt. It always seems to drop right at the 4000rpm mark and shoot back up. I think it is due to windage to be honest. At first I thought it might have been the bearings, but it continued after I replaced everything. It hasn't hurt me yet.
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Old 03-27-2010, 10:15 AM   #17
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Mine does this too. I got a Melling 10554 w/ white spring and the gauge bhavior looks like an inverse bell curve.
Someone define windage please.
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Old 03-27-2010, 10:33 AM   #18
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with 6 quarts in it, no problem now. i knew 7 qts was going to be a problem
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Old 03-27-2010, 01:34 PM   #19
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Could also be the oil climbing the rear of the pan, I installed a $10 Moroso rear pan baffle just for this reason.
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Old 03-27-2010, 08:48 PM   #20
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Quote:
Originally Posted by 97Z28SS View Post
Could also be the oil climbing the rear of the pan, I installed a $10 Moroso rear pan baffle just for this reason.
I think my 4K drop is g-force induced.
2K-4K = 50#
4.1K-5.5K = 35#
5.6K -6.5K = 50#


Most stupid question ever cause maybe I am not capable of reading my dipstick.

This is what my dipstick markings looks like.
ADD●xx●xx●xx●◄──OPERATING RANGE●


The level on my dipstick is here, should it be further to the right:
ADD●xx●xx●xx●◄──OPERATING RANGE●
_____________/\


Example A
Is this condidered absolute full:
ADD●xx●xx●xx●◄──OPERATING RANGE●
_______________________________/\


Example B
Is this condidered absolute full:
ADD●xx●xx●xx●◄──OPERATING RANGE●
____________/\

Dont rip me to bad guys.

Last edited by wrd1972; 03-27-2010 at 08:55 PM.
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